The present invention relates to media devices. More particularly, the present invention relates to torque measurement of media devices.
The force required to rotate one component about an axis is relevant in a number of industries. For example, precision shaft bearings for aircraft subassemblies, electric air motors, hydraulic and pneumatic pumps, and magnetic tape and disk drives include one or more components requiring torque resistance to be within a predetermined limit. For this reason, test equipment including a torque measurement device, such as a torque gauge or transducer, is employed to measure one component during its rotational movement relative to another component.
Presently, tape cartridges (or tape cassettes or media devices) can include a door to access the magnetic tape within. The tape cartridge door is opened and closed by rotation about a fixed pivot point. The force applied to open and/or close a tape cartridge door should be within a certain range. Excessive force may damage the door or nearby components of the tape cartridge or tape drive. Too little force may be insufficient to close the door.
The force required to operate the cartridge door can be tested using pull-testing equipment. The pull-testing equipment pulls the cartridge door open while measuring forces over a range of door rotation. In FIG. 1, there is shown a tape cartridge 100 during force measurement. A cartridge door 102 of the tape cartridge 100 is pulled open about a door hinge pivot point 104. A pulling mechanism of the pull-testing equipment contacts the door 102 and applies a vertical upward force to pull open the door 102.
In order to continuously apply the vertical upward force, the pulling mechanism moves along the door 102 in a direction away from the door hinge pivot point 104 as the rotation angle of the door increases. Hence, for each rotation angle, the force is measured at a different distance from the door hinge pivot point 104. For example, when the pulling mechanism is in contact with the door 102 at a point 106, the distance between the point 106 and the door hinge pivot point 104 is D1 and the force measured is F1. When the pulling mechanism is in contact with the door 102 at a point 108, the distance is D2 and the measured force is F2. The distances D1 and D2 are not equal to each other.
The measured distances and forces, which change simultaneously for each rotation angle, must then be converted or interpreted into a format that is usable as torque measurements. The measured forces, for example, may need to be provided in a graphical form to take into account the different distances or the vector force components.
Thus, it would be beneficial to obtain direct outputs of torque measurements during media device door testing. Moreover, a testing system that permits automatic or semi-automatic testing and direct measurements of a plurality of tape cartridges, media devices, and/or one or more open door positions for each tape cartridge would be beneficial.
In the drawings, to easily identify the discussion of any particular element or part, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced (e.g., element 1104 is first introduced and discussed with respect to FIG. 11).
The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.